The answer to the first 1 is yes yes yes and yes
Answer:

Step-by-step explanation:
<em><u>Identity Used </u></em>: 

Answer:
a = a
b = b
c = c
Step-by-step explanation:
Formula: 
C is always the largest number
<em><u>a times a + b times b = c times c</u></em>
In mathematics, a set A is a subset of a set B, or equivalently B is a superset of A, if A is "contained" inside B. I belive the correct answer from the choices listed above is the second option. It is the set {5, 6, 7} that is a subset of <span> {1, 3, 5, 7, 9}. Hope this answers the question</span>
Polynomial with real coefficients always has even number of complex roots. We know that one of them is 2 + 5i so the second one will be 2 - 5i and:

Answer B.